Safety control mechanism for liquid-fuel burners



g w. w. WILLIAMS SAFETY CONTROL MECHANISM FOR LIQUID FUEL BURNERS Filed Dec. 1. 1924 2 Sheets-Sheet l Aug. 2,1927. 7 1,637,670

w. w. WILLIAMS SAFETY CONTROL MECHANISM FOR LIQUID FUEL BURNERS Filed Dec. 1, 1924 2 Sheets-Sheet 2 q \n N m Q I l l A E l x N t J N Patented Aug. 2, 1927.

UNITED STATES 1,637,670 PATENT OFFICE.

WALTER W. WILLIAMS, OF BLOOMINGTON, ILLINOIS,

ILLINOIS.

SAFETY CONTROL MECHANISM FOR LIQUID-FUEL BURNEBS. I

Application filed December 1, 1924. Serial No. 753165.

My invention relates to liquid fuel burners and more particularly to automatic safety control mechanism in' connection therewith.

The object of my invention is in the provision of automatic safety control, mechanism for liquid fuel burners wherein a stack control of the thermal type is used.

Another object of my invention is in the provision of an automatic safety control mechanism for liquid fuel burners for controlling the operation thereof upon initial failure of ignition or upon a cessation of combustion conditions thereafter by means of a combined stackthermostat and valve control means in the fuel line.

A further object of my invention is in the provision of automatic safety control mechanism for liquid fuel burners comprising valve means in the fuel line controlled by a stack thermostat and a float member in the fuel supply controlling the operation of the burner.

Other objects of my invention will appear in the following specification taken in con nection with the annexed drawings in which Fig. 1 is a diagrammatic view showing the burner generally and safety control mechanism in connection therewith.

Fig. 2 is a view showing a modification of the control mechanism with a more detailed figure in side elevation of the fuel burner; and

Fig. 3 is a cross-sectional view of the atomizing chamber in the fuel burner.

Referring to the drawings, I have illustrated, in Fig. 1, an automatic safety control mechanism including electrically controlled mechanism, while in Fig. 2 the same principle of control is disclosed with a mechanical action instead of electric.

Although the present invention relates to safety mechanism for fuel burners and would be adaptable to any type of the well known domestic burners, nevertheless, a eneral description of the fuel burner descri ed is included.

The burner described in the present application and with which the safety control 30 mechanism is combined has been fully described in a patent bearing the Number 1,451,798, but, as explained above, the following description is given:

An electric motor 1s shown at 10, said motor providing the power for the following named operating portions, suitably attached thereto:

A fan housing 11 encloses a fan member (not shown) which provides added draft for the burner through the housing 12. The axis of the fan (not shown) is an extended portion of the axis of the electric motor.

An-atomizing chamber 13 is shown in detail in Fig. 3. and is constructed as follows:

The extended axis 14 of the electric motor 10, also, provides the power element for the atomizing chamber, and there is attached to said axis a rotor 15 containing, in a slidable manner therein vanes 16. The rotor 15 is eccentrically mounted with relation to an outer casing or housing 17 suitably attached to the electric'motor.

ASSIGNOR r0 WILLIAMS oni-oenerally, the operation of the device is as follows:

Fuel is induced, by action of the rotor 15, into the atomizer through tubes or pipes 18 and 19. Adjacent the fuel inlet, and connecting therewith, is an air intake 20. Rotating action of the atomizer induces a combined inflow of fuel and air, with the result that atomization takes place therein, and the resultant fuel mixture is discharged, under pressure, through the tube 21 to the nozzle or discharge end 22 of the burner.

The above is merely a general description of the burner, but in view of the detailed disclosure and description in the cited patent, it is though sufficient.

Ignition of the discharged fuel mixture may take place in any manner, but the one described herein is by means of a simple jump spark mechanism, including the electrodes 23 located adjacent the discharge end of the burner and having electrical connection with a formal spark coil 24 in the electrical circuit of the device.

Referring to Fig. 1, the safety control mechanism described therein is made up of the following portions:

A main fuel supply pipe 25 from any conventional container (not shown) has mounted therein a formal valve member 26. A crank adapted to open and close said valve is shown at 27, the outer end of which is connected at 28 to the core 29 of a formal solenoid winding 30. The solenoid 30 is in circuit through the wire 31 with a stack thermnstat generallydescribed as 32., This it -municates with a chamber 37 which, also,

has a connection 38 with the atomizing chamber of the burner, however, through formal strainer mechanism shown at 39.

Located in-the chamber or reservoir 37 is a float member 40, the same being pivoted at 41 and having an extended contact arm'42 making or breaking of an electrical circuit through the switch 43. The electrical connection through the knife switch 43 includes in said circuit the electric motor of the burner through the wires 44 and 45.

Inasmuch as the present application is directed to the safety control mechanism and not to the automatic means for controlling the burner, only such general description of said operation will be given as will include the operation of the fuel burner, or rather the electrical circuit thereto.

A house thermostat of formal design is shown at T and a relay switch, at R. A formal transformer X is, also, shown as well as line connections LL from any well known source of electrical supply.

The operationof the burner is controlled by the house thermostat through the relay, and the float mechanism, previously described, isadapted to break the electrical circuit to the motor when the float 40 is in a lower-most position.

Normally, the reservoir 37 will be filled with fuel, at least, to a level that will maintain the electrical circuit throu h the knife switch and, hence, the motor. o'wever, any continued activity of the burner after closure of the valve 26 will result in the uti-' lizing of thisi'eserve supply of fuel and, hence, downward movement of the float until the electrical circuit to the motor is broken by the disengagement of the contact member42 with the knife switch 43.

The operation of the structure shown in Fig. 1 is as follows:

Initial activity of the burner, induced by movement of the house thermostat and relay, results, also, in the operation ofthe ignition mechanism, in the present instance, a jump spark, although any ignition means might be substituted therefor.

Normally, almost immediate ignition of the discharging fuel mixture will take place, the stack thermostat, which is sensitive to combustion conditions, will be operated to .close the electrical circuit through the contact points 35 and 36, with the result that energizing of'the solenoid 30 will take place and, hence, upward movement of the core 29 and a consequent opening of the valve 26 to permit the uninterrupted flow of fuel through the line 25 and,hence, through the reservoir 37 to the burner.

An overflow pipe has been described as 46 to take care of excess quantities of fuel in the reservoir. Naturally, upon an lllltlal movement of the burner, the fuel in the reservoir will' supply the burner, but after the action of the stack thermostat, fuel will be furnished from the main supply line.

The above describes the natural and normalmovement of the burner. However, in case of an initial failure of ignition and, hence, failure of combustion conditions, the supply of fuel in the reservoir will soon be absorbed and the float therein will eventually assume the dotted line position shown in Fig. 1, with the result that the electrical circuit to the motor will be broken by the disengagement of the contact member 42 with knife switch 43.

Also, in case of a failure of combustion conditions, after the initial activity of the burner, there will be a cooling down of the stack thermostat which will result in the breaking of the electrical circuit through the contact points 35 and 36, with-the result that the solenoid 30 will release the core 29 and, hence, permit the valve 26 to be closed, thereby cutting off the fuel supply.

Closing of the valve during activity of the burner will result in the gradual absorption of the-reserve fuel supply in the reservoir 37 and, finally, in the breaking of the electrical circuit to the motor through the disengagement of the contact member 42 with the knife switch 43.

Referring to the modification shown in 2, the only difference is in the matter of structure, wherein, instead of having an electrical connection between the valve member and the stack thermostat, there is a mechanical connection in the cable or wire 47. The thermostat is, also, changed, and the expansion of the thermal rod 48. due to the action of heat, operates to open and close the valve 26. Inasmuch as the operation of the modification, in principle, is exactly that of the structure shown in F ig. 1, no further description ofthe operation is thought necessary.

The present device, or rather devices, were improvised to take the place of safety controls of a rather similar type, that is, where a stack thermostat was used.

These former devices are entirely electrical, requiring intricate and expensive structure to provide the timing element which is provided in the present instance in the sim ple float member. The obvious saving in tion of the operation of the projecting means, including a thermostat located in a manner to be responsive to combustion conditions, a valve member in the fuel line controlled thereby, and a fuel reservoir including therein a float member controlling the electric circuit to the electrically operated means.

2. In a liquid fuel burning device, in C0111- bination, electrically operated means for projecting a mixture of air and sprayed fuel into a zone of ignition, means for igniting same, and automatic safety control mechanism operating upon an initial failure of ignition or upon a cessation of combustion conditions to prevent or cause a cessation of the operation of the projecting means, in-

cluding a member located in a manner to be responsive to combustion conditions, a valve member in the fuel line controlled thereby, and a reserve supply chamber adapted to supply the projecting means temporarily upon closure of the valve member, said chamber having a float member therein controlling the electrical circuit to the electrically operating means.

3. In an electrically operated liquid fuel burning device, in combination, electrically actuated automatic safety mechanism for controlling the operation of the burner either upon an initial failure of ignition or upon a cessation of combustion conditions to prevent or cause a cessation of the operation of the lmrner mechanism, including a stack theremostat,-a valve member in the fuel line controlled thereby, and a ieserve fuel supply temporarily supplying the burning device upon commencement of operation or upon a closure of the fuel valve thereafter, said reserve fuel supply having mechanism in connection therewith and controlled by the supply of fuel therein for opening the circuit to the burner after adetermined amount of the reserve fuel has been used.

4. In an electrically operated liquid fuel burning device, in combination, electrically actuated means for projecting a mixture of air and sprayed fuel into a zone of ignition,

means for igniting same, and automatic safety mechanism operating upon an initial fail-- me of ignition or upon a cessation of combustion conditions to. prevent or cause a cessation of the operation of the burning device, said safety mechanism including a stack thermostat, a valve member controlled thereby, and a reserve fuel supply chamber adapted to temporarily supply the burning device upon commencement of operation or upon a closure of the valve member after initial opening, said reserve supply chamber having mechanism adapted to open the cir- 'cuit to the fuel burning device upon an exhaustion of the reserve fuel supply.

5. In a liquid fuel burning device, in combination, electrically operated means for projecting a mixture of air and sprayed fuel into a zone of ignition, means for igniting same, and electrically actuated automatic safety mechanism operating upon an initial failure of ignition or upon a cessation of combustion conditions to prevent or cause a cessation of the operation of the projecting means, said mechanism including a member in the electric circuit responsive to combustion conditions, a valve member in the fuel line included in the electric circuit with said member and controlled thereby, and a reserve fuel supply chamber adapted to supply the projecting means upon closure of the valve member for a temporary period and a float therein operating after a determined time to stop the operation of the electrically operated means upon failure of the valve to open.

6. In a liquid fuel burning device, in combination, electrically operated means for projecting a mixture of air and sprayed fuel into a zone of ignition, means for ignitmg same, and electrically actuated automatic safety mechanism operating upon an initial failure of ignition or upon a cessation of combustion conditions to prevent or cause a cessation of the operation of the projecting means, including a thermal member in C11- euit therewith located in a manner to be responsive to combustion conditions, a valve WALTER W. WILLIAMS. 

